a lot of people use chat to insult other players and other people rightfully don't want to see that but you want to say hello so I guess we should make it impossible to disable chat...
It should be impossible to disable chat.

That is a crude idea .>>>>people who disable chat should play with other people who disable chat but chess.Com staff .>>> not contactable

And at the end of every game you should be able to rate the other player 1 to 5 stars
I would agree. I enjoy playing against opponents that chat and play nice. Your rating should be how they play and socialness. I have had fun games against both 700 and 1900 rated players and "omg should I just resign because I cannot stand this guy" games against 1200 players.
I play in focus mode. All I see is your avatar and flag. I don't even see your rating. I certainly don't want chit chat.